Аннотация:Photometric observations of the AM Her system (4U 1813 + 50) have been made with 1-sec time resolution. The data are analyzed statistically. Flares recur at a mean frequency of 0.5 + 0.3/sec and contain 0.3 + 0.2 of the energy radiated. This rapid variability may be associated with the cyclotron component of the emission.